摘要 |
In continuous friction-actuated extrusion, especially Conform extrusion of copper, at least part of the tooling is made from aged nickel-chromium base alloy (which is preferably cold-worked before aging to give a yield strength of at least 1500 MN/m2 at 20 DEG C.) and which is capable of sustaining an adherent oxide film. The preferred alloy is "Inconel Alloy 718". Despite lower hardness, the tooling has better service life than conventional special-steel tooling. |